Revenues - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Capitalized Contract Cost [Line Items]
Passenger ticket revenues	$ 50,914,000	$ 175,605,000	$ 92,928,000	$ 2,208,355,000
Customer refunds	107,900,000		107,900,000		$ 95,800,000
Contract liability	283,700,000		283,700,000		124,800,000
Contract asset	53,700,000		53,700,000		53,700,000
Commission, transportation and other
Capitalized Contract Cost [Line Items]
Prepaid travel agent commissions	31,700,000		$ 31,700,000		$ 1,100,000
Minimum
Capitalized Contract Cost [Line Items]
Length of cruise			2 days
Maximum
Capitalized Contract Cost [Line Items]
Length of cruise			24 days
Port Costs
Capitalized Contract Cost [Line Items]
Passenger ticket revenues	$ 3,200,000	$ 0	$ 4,700,000	$ 124,500,000